| Abbreviation | Definition |
|---|---|
| OSU | Overated State University |
| OSU | Overrated State University |
| OSUM | Ohio State University Mathematics |
| OSUM | Optics Society at the University of Michigan |
| OSY | Outstanding Student of the Year |
| OTC | Occupational Training Center |
| OTD | Office of Technology Development |
| OTI | Office of Technology Integration |
| OTR | On Time Reporting |
| OTS | Oxford Traffic Strategy |
| OU | Oakland University |
| OU | Oakland University (Pontiac, Michigan) |
| OU | Ohio University |
| OU | Oklahoma University |
| OU | Open University |
| OU | Osmania University |
| OU | Ottawa University |
| OU | Ouachita University |
| OU | Overrated University |
| OU | Oxford University |